Three dimensional intravascular ultrasonic assessment of the local mechanism of restenosis after balloon angioplasty

OBJECTIVE: To assess the mechanism of restenosis after balloon angioplasty. DESIGN: Prospective study. PATIENTS: 13 patients treated with balloon angioplasty. INTERVENTIONS: 111 coronary subsegments (2 mm each) were analysed after balloon angioplasty and at a six month follow up using three dimensional intravascular ultrasound (IVUS). MAIN OUTCOME MEASURES: Qualitative and quantitative IVUS analysis. Total vessel (external elastic membrane), plaque, and lumen volume were measured in each 2 mm subsegment. Delta values were calculated (follow up - postprocedure). Remodelling was defined as any (positive or negative) change in total vessel volume. RESULTS: Positive remodelling was observed in 52 subsegments while negative remodelling occurred in 44. Remodelling, plaque type, and dissection were heterogeneously distributed along the coronary segments. Plaque composition was not associated with changes in IVUS indices, whereas dissected subsegments had a greater increase in total vessel volume than those without dissection (1.7 mm(3) v -0.33 mm(3), p = 0.04). Change in total vessel volume was correlated with changes in lumen (p < 0.05, r = 0.56) and plaque volumes (p < 0.05, r = 0.64). The site with maximum lumen loss was not the same site as the minimum lumen area at follow up in the majority (n = 10) of the vessels. In the multivariate model, residual plaque burden had an influence on negative remodelling (p = 0.001, 95% confidence interval (CI) -0.391 to -0.108), whereas dissection had an effect on total vessel increase (p = 0.002, 95% CI 1.168 to 4.969). CONCLUSIONS: The mechanism of lumen renarrowing after balloon angioplasty appears to be determined by unfavourable remodelling. However, different patterns of remodelling may occur in individual injured coronary segments, which highlights the complexity and influence of local factors in the restenotic process

Clinical outcomes after treatment of multiple lesions with zotarolimus-eluting versus sirolimus-eluting coronary stents (a SORT OUT III substudy)

<p>Abstract</p> <p>Background</p> <p>Data on clinical outcomes among patients treated with the zotarolimus-eluting Endeavor™ stent versus the sirolimus-eluting Cypher™ stent favor the sirolimus-eluting stent. However, a separate comparison of clinical outcome among patients treated for multiple lesions with these stents is lacking. We performed this comparison within the SORT OUT III trial data set.</p> <p>Methods</p> <p>Among 2332 patients randomized in SORT OUT III, 695 were treated for multiple lesions with zotarolimus-eluting (n = 350) or sirolimus-eluting (n = 345) stents and followed for 18 months. Major adverse cardiac events (MACE); composite of cardiac death, myocardial infarction, or target vessel revascularization (TVR); was the primary endpoint.</p> <p>Results</p> <p>Zotarolimus-eluting compared to sirolimus-eluting stent treatment was associated with increased MACE rate (13.2% vs. 2.6%; hazard ratio 5.29 with 95% confidence interval: 2.59-10.8). All secondary endpoints; all cause death, cardiac death, myocardial infarction, TVR, target lesion revascularization, in-stent restenosis, and definite stent thrombosis; were observed more frequently among zotarolimus-eluting stent treated patients. For all endpoints, hazard ratios were 1.6 to 4.6 times higher than in the overall results of the SORT OUT III trial.</p> <p>Conclusions</p> <p>We observed better clinical outcomes among patients treated for multiple lesions with the sirolimus-eluting stent compared to those treated with the zotarolimus-eluting stent.</p